eHam

eHam Forums => Elmers => Topic started by: N1VL on December 13, 2009, 03:09:19 PM



Title: Ham Radio science project ideas needed for 12 yr.
Post by: N1VL on December 13, 2009, 03:09:19 PM
Hi,

I posted this in youth, but there is not as much traffic there. Hope this is ok.

my 12 year old son is a licensed tech and is starting his science project for school. He really wants to do something related to ham radio. His older sister built a 3 el, 2 el yagi and a dipole and then field tested and compared them. He can't come up with any ideas. Some guidelines:
1. It must have a hypothesis and follow the scientific method. Building a kit or an antenna will not work. The term project is misleading - it must have experimental nature to it, but a project (building something) is great if it can be combined.
2. It shouldn't be very expensive

I am hoping some of you might have some ideas?

Thanks!
Steve


Title: RE: Ham Radio science project ideas needed for 12
Post by: W5FYI on December 13, 2009, 03:56:03 PM
How about a regenerative receiver, something like Paul Harden's Pip Squeak or one of Charles Kitchen's designs. Hypothesis could be LED stability vs that of the typical diodes used in these kinds of receivers (e.g. substituting LEDs for the 1N914 diodes in the Pip Squeak's regulation chain).

Your son might also want to work on laser communications, red vs green vs blue lasers. Hypothesis might be along the lines that red signals would be attenuated less by the atmosphere (based on fact that sunsets are more red, than green or blue). He might be able to find the optimum wavelength for laser ranging.

Keep us informed.


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: WA1RNE on December 13, 2009, 04:03:06 PM
Ask him if he wants to build a crystal radio.

 As you probably know, hams started out as experimenters on the 200 meter band, the current AM broadcast band.


 ...WA1RNE


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: N1VL on December 13, 2009, 04:09:58 PM
Yes! Thanks, however, we need and experiement with a hypothesis - nut just a build. We have thought of a lot of things to build, but we need to experiement - compare, etc.

Steve


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: N1VL on December 13, 2009, 04:18:55 PM
Cool ideas - I will start reasearching to see if possible. Keep the ideas coming!!!

Thanks :)


Title: RE: Ham Radio science project ideas needed for 12
Post by: K7PEH on December 13, 2009, 04:20:35 PM
How about something like showing the different ways that electromagnetic waves can be created.  First thing to do is to make sure you have a good receiver to use (Ideally, one where you can show a spectrum of the signals, such as Icom, SDR, etc.).

Then, using everyday items such as a vacuum cleaner (get an RF dirty one), spark coil, touch lamp, noisy neon sign, and so forth.  Then, show by turning these on and off that they create electromagnetic waves and maybe the experimental side is even to use the receiver as a means of showing the frequency and noise characteristics (one reason a spectrum display might be useful).


Title: RE: Ham Radio science project ideas needed for 12
Post by: KA5N on December 13, 2009, 04:41:45 PM
I went to a Science Fair in my high school days (I was already a ham)and one of the entrants did a study showing that electromagnetic waves did indeed consist of a magnetic wave portion and an electric wave portion.  His setup included detectors and various types of shielding designed to separate an eletromagnetic wave into two different parts.  
It was interesting and the young fellow doing the study showed a creative bent in his methods.

Or he could build a interociter (See Raymond F. Jones
"This Island Earth" for more information).

Allen


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: KE3WD on December 13, 2009, 04:50:51 PM
The ypothesis is always the hard part, but with children it is usually better to ask the child what they might be wondering about and guide from there.  I'm sure the lad has some unanswered questions about radio, maybe propagation, maybe something about how the circuits or one of the circuits works, or it could even perhaps have something to do with the more human aspects of the hobby such as exploring the data and finding out how many young licensed radio amateurs have ended up being engineers, scientists, doctors and teachers.  Or just about anything else.  ASK HIM.  Sometimes children don't yield an answer right away, let him know that its alright to think about it and come back with an answer, too.  

OR

His hypothesis could be, "50% or more licensed radio amateurs don't seem to know what the word hypothesis means or suffer from reading comprehension problems."


And he could use this thread for his data source.  

LOL


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: N3OX on December 13, 2009, 07:25:36 PM
I'm sure the lad has some unanswered questions about radio, maybe propagation

Propagation could give a pretty good source for non-obvious and fun-to-test hypotheses... for example, you could come up with a testable hypothesis regarding the relative simplex range between two 2m/70cm handhelds...  

You could gather data to test hypotheses based on a couple different sets of surroundings.  Maybe someplace with buildings and another out in the woods?  You could use some GPS to track positions while you run tests.

Instead of hypothesizing which RF frequency would work better, you could hypothesize which of vertical or horizontal polarization would give more range in a given set of circumstances...

There are some opportunities for some surprising results here, which I prefer.  I don't mind much if my hypotheses are wrong as long as I learn something interesting in the end!

73
Dan





Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: N4JTE on December 13, 2009, 09:13:02 PM
I think he should check with his sister for advice not us, hi


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: TANAKASAN on December 14, 2009, 09:20:48 AM
How about setting up an experiment showing the change in MUF over a 24 hour period. This could cover lots of stuff including the different layers in the Ionosphere and how they alter over a day/night cycle.

Tanakasan


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: N1DVJ on December 14, 2009, 09:57:59 AM
Consider one the ham radio kits for models.  Like model rocketry.  You can pick up small kits that record G forces, altitude, temp, whatever, and transmit it to the ground fairly cheap.  And with a lot of the kits, the data is just a tone, so you can record it with a PC with a sound card hooked to a receiver.


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: DXZEPP on December 15, 2009, 12:51:34 PM
How about something to do with the speed of sound. ex. the time it take for your voice or a tone to reach a microphone. You could set up a speaker/oscillator to generate a test tone and set a microphone a known distance away. Then measure the time differance between the oscillator tone is activated and the time the microphone receives ths signal.
You could build a simple 2Khz oscillator to drive the speaker, and the only other thing needed is a 2 channel oscilloscope - if you don't have a scope maybe your Ham club or fellow Ham.  

Good luck  

Bob


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: CLEBOT on December 15, 2009, 01:49:52 PM
Good afternoon,

How about finding a correlation between radio propagation and the sunspot number?

In order to reduce the number of variables, have him stay on 1 frequency or band and use the same radio, same antenna and monitor that frequency/band at the same time every day.  Then, check Spaceweather.com (www.spaceweather.com) for the daily sunspot number.
Sunspot 1035 is currently moving across the face of the sun.

Below are some IDEAS that might help get him started, or help get him over a tough spot.

His scientific method could go something like this:

State the problem: "Low sunspot numbers reduce the distance that a _______MHz_ (frequency) radio wave can reliably travel at ____:____ (time).

Form Hypothesis: "I think that low sunspot numbers affect radio wave propagation at _____MHz at ___:___ because..."

Design Experiment: "For my experiment, I used a ____(radio) and tuned in to ______ (frequency) at ___:___ UTC.  The antenna I used was built by my dad and me and is... .  I will monitor the same frequency or band every day at the same time and then record the number of sunspots.  I will plot the data on a chart comparing the signal strength vs. the number of sunspots and create a graph."

Test Hypothesis: On the first day, I monitored ___ from ____:____ to ____:____.  I noticed that the signal was very hard to copy..."  Then I checked the number of sunspots and counted ### sunspots.

Evaluate Data: On days with more sunspots, I observed that the signals were stronger and clearer and that I could hear other stations from farther away... ."

Form Conclusion: Based on my observations, I have concluded that the signal strength increases at this frequency when there are more sunspots.  This is because... ."  "Addtionally, I noticed that if I changed frequencies or listened at a different time of day, it affected the signal strength."  However, since this was a comparison between sunspots and signal strength... ."

Variables/sources of error: Weather, dimmer switches, etc.

You could uses something reliable, like WWV for a time signal and measure the S-unit or signal strength from day to day.

This might be a little difficult, seeing as there have been so few sunspots lately.

Good luck and hope this helps.  Drop me a line at the high school radio club if you need anything else (tigerhams@yahoo.com)

Gerrit Rickwalt, KE5HVM
Conroe High School
Astronomy/Physics teacher
Sponsor, Conroe High School Amateur Radio Club, K2CHS
www.tigerhams.com


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: CLEBOT on December 15, 2009, 01:57:08 PM
Oops!
The e-mail should be tigerhams@yahoo.com and NOT www.tigerhams.com.  It's been a long day.  Time to go home!

Good luck and '73!


Title: RE: Ham Radio science project ideas needed for 12
Post by: AG6WT on December 15, 2009, 02:32:17 PM
To continue with Gerrit's idea, having your son sit by the radio recording stations he can hear might be difficult if his time on the radio is limited or if he can't do repeated sessions under similar conditions.

One thing that might help is to collect data on contacts that are posted on the internet and used that to support or refute his hypothesis.

One website that might help is http://pskreporter.info. There you'll find digital mode contacts around the world broken down by band and time block. The data is plotted on google maps that might make a nice display if your son is making a poster.

73
Ray


Title: RE: Ham Radio science project ideas needed for 12
Post by: NI3S on December 15, 2009, 03:46:46 PM
Coax Cable test would be cheap and easy to setup.  Basic instruments and borrowed samples for testing.


Title: RE: Ham Radio science project ideas needed for 12
Post by: N0SOY on December 16, 2009, 09:21:10 PM
Google Crystal radio and you will be amazed the detail and complexity that shows up.  Those can provide hours of experimentation.  

Just don't plug them in.  Bad things happen.  I know.


Title: RE: Ham Radio science project ideas needed for 12 yr.
Post by: WA4CUA on December 17, 2009, 09:40:30 AM
Here is an idea:

01). First, convert an old AM radio to a transmitter (actually it is already, with the local oscillator). The local oscillator is 455 Khz above the radio station frequency, so if it is tuned to 600 Khz, for example, it is "transmitting" at 1055 Khz, and can be picked up using a nearby AM receiver. Adding a small antenna to the local oscillator circuit will help the transmitting distance.

02). Place the radio on a metal plate. Now comes the experiment:

03). Make several covers for the radio (cardboard, perforated screen (metal colander) full metal jacket (soup pan), ceramic dish, etc. that will fit over the radio. The experiment can be to analyze the various radio wave attenuation properties of the various coverings.

It would help if the radio receiver outside the "transmitter" had an "S" meter that could be used to show the relative attenuation percentages (and also show how LOG scales are used, since, I believe, the typical "S" meter is calibrated in LOGbase10).

Alternately, if the signal is strong enough, you might be able to build a sensitive signal-strength meter with a diode and a very sensitive meter (or perhaps use a sensitive voltmeter; some can be purchased on sale for as cheap as $1.95 at Harbor Freight Tools). Then the display should be linear, which is easier to track than LOGbase10 values.

If you really wanted to make a stronger transmitter from the AM radio, you could retune the local oscillator down to the IF frequency of 455 Khz, and would have a much stronger signal at the end of the IF stages for transmitting.

Have Fun!

John
WA4CUA